Ophthalmic lenses for treating myopia

ABSTRACT

Eyeglasses are disclosed that include eyeglass frames and a pair of ophthalmic lenses mounted in the frames. The lenses include a dot pattern distributed across each lens, the dot pattern including an array of dots spaced apart by a distance of 1 mm or less, each dot having a maximum dimension of 0.3 mm or less, the dot pattern including a clear aperture free of dots having a maximum dimension of more than 1 mm, the clear aperture being aligned with a viewing axis of a wearer of the pair of eyeglasses.

CROSS REFERENCE

This application is a continuation of PCT application Serial NumberPCT/US2017/044635 filed Jul. 31, 2017, which claims priority to U.S.Provisional Application Ser. Nos. 62/369,351 filed Aug. 1, 2016 and62/502,995 filed May 8, 2017.

FIELD OF THE INVENTION

The invention features ophthalmic lenses for treating myopia, methodsfor forming such lenses, methods for using such lenses, and methods formonitoring the efficacy of such lenses.

BACKGROUND

The eye is an optical sensor in which light from external sources isfocused, by a lens, onto the surface of the retina, an array ofwavelength-dependent photosensors. Each of the various shapes that theeye lens can adopt is associated with a focal length at which externallight rays are optimally or near-optimally focused to produce invertedimages on the surface of the retina that correspond to external imagesobserved by the eye. The eye lens, in each of the various shapes thatthe eye lens can adopt, optimally or near-optimally, focuses lightemitted by, or reflected from external objects that lie within a certainrange of distances from the eye, and less optimally focuses, or fails tofocus objects that lie outside that range of distances.

In normal-sighted individuals, the axial length of the eye, or distancefrom the lens to the surface of the retina, corresponds to a focallength for near-optimal focusing of distant objects. The eyes ofnormal-sighted individuals focus distant objects without nervous inputto muscles which apply forces to alter the shape of the eye lens, aprocess referred to as “accommodation.” Closer, nearby objects arefocused, by normal individuals, as a result of accommodation.

Many people, however, suffer from eye-length-related disorders, such asmyopia (“nearsightedness”). In myopic individuals, the axial length ofthe eye is longer than the axial length required to focus distantobjects without accommodation. As a result, myopic individuals can viewnear objects clearly, but objects further away are blurry. While myopicindividuals are generally capable of accommodation, the average distanceat which they can focus objects is shorter than that for normal-sightedindividuals.

Typically, infants are born hyperopic, with eye lengths shorter thanneeded for optimal or near-optimal focusing of distant objects withoutaccommodation. During normal development of the eye, referred to as“emmetropization,” the axial length of the eye, relative to otherdimensions of the eye, increases up to a length that providesnear-optimal focusing of distant objects without accommodation. Ideally,biological processes maintain the near-optimal relative eye length toeye size as the eye grows to final, adult size. However, in myopicindividuals, the relative axial length of the eye to overall eye sizecontinues to increase during development, past a length that providesnear-optimal focusing of distant objects, leading to increasinglypronounced myopia.

It is believed that myopia is affected by behavioral factors as well asgenetic factors. Accordingly, myopia may be mitigated by therapeuticdevices which address behavioral factors. For example, therapeuticdevices for treating eye-length related disorders, including myopia, aredescribed in U.S. Pub. No. 2011/0313058A1.

SUMMARY

Eyeglasses and contact lenses are disclosed that reduce signals in theretina responsible for growth of eye length. Exemplary embodiments aremade using polycarbonate or Trivex lens blanks which have been treatedby applying a pattern of clear liquid plastic protuberances that thatare hardened and bonded to the lens by ultraviolet light. Each clearplastic protuberance has a refractive index similar to the underlyingpolycarbonate to which it is bonded so in the location of theprotuberance it and the underlying lens act as a single optical element.The array of such optical elements behave as a highly aberrated lensarray dispersing light transmitted by the array fairly uniformly in alldirections. The result is a reduction in contrast in a retinal image.The eyeglass lenses have apertures free from protuberances located onthe lens axes allowing a user to experience maximal visual acuity whenviewing on-axis objects, while objects in the periphery of the user'svisual field are viewed with reduced contrast and acuity.

In one example, an image on the retina consists of the normally focusedimage with an average intensity of 74% of what would be produced by thelens without the protuberance array. Superimposed on the focused imageis a background of uniform retinal illumination equal to 25% of theaverage luminance of the normally focused image.

For these eyeglasses, the focused image is reduced in contrast comparedto that normally used to correct (but not treat) refractive errors. Theexact amount of contrast reduction depends on the relative amount ofdark and light areas in the image being transmitted. For the exampleabove, where 24% of the light is dispersed uniformly, the maximumcontrast reduction would be 48% where contrast is defined as theLuminance difference/Average luminance. Experiments demonstrate thatthis amount of reduction in contrast has significant effects on thephysiology of the eye related to mechanisms responsible for controllingthe growth of eye length.

Various aspects of the invention are summarized as follows:

In general, in a first aspect, the invention features a pair ofeyeglasses, including: eyeglass frames; and a pair of ophthalmic lensesmounted in the frames. The lenses include a dot pattern distributedacross each lens, the dot pattern including an array of dots spacedapart by a distance of 1 mm or less, each dot having a maximum dimensionof 0.3 mm or less.

Implementations of the eyeglasses may include one or more of thefollowing features and/or features of other aspects. For example, eachdot can have a maximum dimension of 0.2 mm or less (e.g., 0.1 mm orless, 0.05 mm or less, 0.02 mm or less, 0.01 mm or less). In someembodiments, each dot is substantially the same size. The dots may bespaced apart by 0.8 mm or less (e.g., 0.6 mm or less, 0.5 mm or less,0.4 mm or less, 0.35 mm or less). The dots may be arranged on a squaregrid, a hexagonal gird, another grid, or in a semi-random or randompattern. The dots may be spaced at regular intervals, e.g., such as 0.55mm, 0.365 mm, or 0.24 mm. Alternatively, dot spacing may vary dependingon the distance of the dot from the center of the lens. For example, dotspacing may increase monotonically or decrease monotonically as thedistance from the center of the lens increases.

The dot pattern can include a clear aperture free of dots having amaximum dimension of more than 1 mm, the clear aperture being alignedwith a viewing axis of a wearer of the pair of eyeglasses. The clearaperture can have a maximum dimension (e.g., a diameter) of 2 mm or more(e.g., 3 mm or more, 4 mm or more, 5 mm or more, 6 mm or more, 7 mm ormore, 8 mm or more) and up to 1.5 cm (e.g., 1.5 cm or less, 1.4 cm orless, 1.3 cm or less, 1.2 cm or less, 1.1 cm or less, 1.0 cm or less).The clear aperture can be substantially circular or a similar shape,such as octagonal, square, or other polygon shape.

In some embodiments, the dots are protrusions on a surface of thecorresponding lens. The protrusions can be formed from a transparentmaterial. In some cases, the transparent material is clear and/orcolorless. Alternatively, or additionally, at least some of thetransparent material can be tinted (e.g., with a dye that absorbs redwavelengths). The transparent material can have substantially the samerefractive index as a lens material. The protrusions can besubstantially spherical or semi-spherical.

In certain embodiments, the dots are recesses on a surface of thecorresponding lens.

The dots can be inclusions between opposing surfaces of each lens.

The lenses can be clear lenses. In some embodiments, the lenses aretinted lenses.

The dot pattern can reduce an image contrast of an object viewed throughthe dot pattern by at least 30% (e.g., by at least 35%, by at least 40%,by at least 45%, by at least 50%, by at least 55%, by at least 60%)compared to an image contrast of the object viewed through the clearaperture. In some embodiments, the lenses have optical power to correcta wearer's on-axis vision to 20/20 or better (e.g., 20/15) through theclear aperture, and, for at least a portion of the wearer's peripheralvision through the dot pattern, the lenses correct the wearer's visionto 20/25 or better, 20/30 or better, 20/40 or better, and the like.

In another aspect, the invention features a method of making theeyeglasses, including: depositing discrete portions a material on asurface of the lens corresponding to the dot pattern; and curing thedeposited material to provide protrusions on the lens surface formingthe dot pattern. The material can be deposited using an inkjet printer.The deposited material can be cured using radiation (e.g., ultravioletradiation).

In general, in another aspect, the invention features a pair ofeyeglasses customized for a wearer, including: eyeglass frames; and apair of ophthalmic lenses mounted in the frames, the lenses havingoptical power to correct the wearer's on-axis vision to 20/20 or better,the lenses including a dot pattern distributed across each lens, the dotpattern including an array of dots arranged so that, for at least aportion of the wearer's peripheral vision, the lenses correct thewearer's vision to 20/25 or better and reduce an image contrast by atleast 30% compared to on-axis image contrast. Embodiments of theophthalmic lens may include one or more of the features of otheraspects.

In general, in a further aspect, the invention features a pair ofeyeglasses customized for a wearer, including: eyeglass frames; and apair of ophthalmic lenses mounted in the frames, the lenses havingoptical power to correct the wearer's on-axis vision to 20/20 or better.The eyeglasses include an optical diffuser distributed across each lens,the optical diffuser being configured so that, for at least a portion ofthe wearer's peripheral vision, the lenses correct the wearer's visionto 20/40 or better, 20/30 or better, or 20/25 or better and reduce animage contrast by at least 30% compared to on-axis image contrast.

Embodiments of the ophthalmic lens may include one or more of thefollowing features and/or features of other aspects. For example, theoptical diffuser can include a film laminated on a surface of each lens.The lenses may each include a clear aperture free of the opticaldiffuser having a maximum dimension of more than 1 mm, the clearaperture being aligned with a viewing axis of a wearer of the pair ofeyeglasses.

In general, in a further aspect, the invention features an ophthalmiclens, including: two opposing curved surfaces collectively having anoptical power to correct a wearer's on-axis vision to 20/20 or better;and a dot pattern distributed across each lens, the dot patterncomprising an array of spaced apart dots arranged so that, for at leasta portion of the wearer's peripheral vision, the lenses correct thewearer's vision to 20/25 or better and reduce an image contrast by atleast 30% compared to on-axis image contrast, the dot pattern includinga clear aperture free of dots aligned with a viewing axis of the wearer.

Embodiments of the ophthalmic lens may include one or more of thefollowing features and/or features of other aspects. For example, theophthalmic lens can be an eyeglass lens. Alternatively, in someembodiments, the ophthalmic lens is a contact lens.

In general, in another aspect, the invention features a method ofmonitoring and arresting myopia progression in a person, including:measuring variations in a thickness of the person's choroid over aperiod of time; and providing the person with ophthalmic lenses whichreduce an image contrast in the person's peripheral vision compared toan on-axis image contrast.

Implementations of the method can include one or more of the followingfeatures and/or features of other aspect. For example, the ophthalmiclenses may be provided in eyeglasses of the foregoing aspects.Alternatively, the ophthalmic lenses may be provided as contact lenses.In some implementations, measuring the variations includes measuring athickness of the person's choroid using Optical Coherence Tomography(OCT).

Among other advantages, disclosed embodiments feature eyeglasses thatinclude features that reduce signals in the retina responsible forgrowth of eye length on the lenses for both eyes, without diminishingthe user's on-axis vision in either eye to an extent that is disruptiveto the user. For example, providing a dot pattern that modestly blursthe wearer's peripheral vision while allowing normal on-axis viewingthrough a clear aperture allows for all-day, every-day use by thewearer. Disclosed embodiments can also provide therapeutic benefits to auser in both eyes using only a single pair of eyeglasses, in contrast toapproaches which involve alternating use of different pairs ofeyeglasses.

Moreover, the dot patterns can be largely unnoticeable to others,particularly where dot patterns are clear and colorless and/or wherecontact lenses are used. The subtlety of the dot patterns can result inmore consistent use by certain wearers, especially children, who mayotherwise be self-conscious during everyday (e.g., at school orotherwise among peers) use of more conspicuous devices.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a pair of eyeglasses containing ophthalmic lenses fortreating myopia.

FIG. 1B shows a dot pattern on the ophthalmic lenses shown in FIG. 1A.

FIG. 2 illustrates contrast reduction experienced using exemplaryophthalmic lenses for treating myopia.

FIG. 3A shows an inkjet printing system for forming dot patterns onophthalmic lenses.

FIG. 3B is a flowchart showing steps in a method for making dot patternsusing the system shown in FIG. 3A.

FIG. 3C shows a printing template for forming a dot pattern using theinkjet printing method of FIG. 3B.

FIG. 3D shows a top view of a jig used for positioning multiple lensesin an inkjet printing system.

FIG. 4 are photographs (A)-(C) showing a dot pattern on an exemplaryophthalmic lens.

FIG. 5 are optical coherence tomographic (OCT) images (A)-(B) of an eyeshowing choroid thickness.

FIG. 6 are OCT images (A)-(D) showing choroid thickness.

FIG. 7 is a plot showing relative choroid thickness as a function ofretinal position for a subject pre- and post-treatment.

FIG. 8 is a photograph showing a dot pattern used in prototype I lenses.

FIG. 9 is a plot comparing results of a study conducted using prototypeI lenses and an Initial Study. The time progression of axial lengthdifference measurements are plotted.

FIG. 10 is a photograph showing a dot pattern used in prototype IIlenses.

FIG. 11 is a photograph showing a dot pattern used in prototype IIIlenses.

FIG. 12 is a bar chart comparing change in diopters after 180 days forsubjects from the Initial Study (“first diffuser”), prototype III lenses(“new diffuser”), and a control group (“no diffuser”).

FIG. 13 is a schematic diagram of a laser system for forming a dotpattern on a contact lens.

FIGS. 14A-B are examples of dot patterns for contact lenses.

FIG. 15A is a photograph of a contact lens with a dot pattern.

FIG. 15B is a photograph of an eyeglass lens with a dot pattern.

DETAILED DESCRIPTION

Referring to FIG. 1A, myopia-reducing eyeglasses 100 are disclosed whichallow treatment of both eyes simultaneously without substantiallycompromising clear vision. Moreover, the eyeglasses are sufficientlyrobust and inconspicuous as to allow a wearer to engage in the sameday-to-day activities without the eyeglasses failing and without feelingself-conscious about their appearance, which is especially desirablebecause the eyeglasses are typically used to arrest eye-lengthening inchildren.

Myopia-reducing eyeglasses 100 are composed of a pair of frames 101 andophthalmic lenses 110 a and 110 b mounted in the frames. Ophthalmiclenses 110 a and 110 b each have a clear aperture 120 a and 120 b,respectively, surrounded by reduced-contrast areas 130 a and 130 b,respectively. Clear apertures 120 a and 120 b are positioned to coincidewith the wearer's on-axis viewing position, while reduced contrast areas130 a and 130 b correspond to the wearer's peripheral vision. Referringalso to FIG. 1B, reduced contrast areas 130 a and 130 b are composed ofan array of dots 140, which reduce the contrast of an object in thewearer's peripheral vision by scattering light passing through thoseareas to the wearer's eye.

The size and shape of the clear aperture may vary. Generally, the clearaperture provides the wearer with a viewing cone for which their visualacuity may be optimally corrected (e.g., to 20/15 or 20/20). In someembodiments, the aperture has a maximum dimension (in the x-y plane) ina range from about 0.2 mm (e.g., about 0.3 mm or more, about 0.4 mm ormore, about 0.5 mm or more, about 0.6 mm or more, about 0.7 mm or more,about 0.8 mm or more, about 0.9 mm or more) to about 1.5 cm (e.g., about1.4 cm or less, about 1.3 cm or less, about 1.2 cm or less, about 1.1 cmor less, about 1 cm or less). Where the aperture is circular, e.g., asdepicted in FIG. 1A, this dimension corresponds to the circle's diameter(i.e., A_(x)=A_(y)), however non-circular (e.g., elliptical, polygonal,A_(x)≠A_(y)) apertures are also possible.

The clear aperture can subtend a solid angle of about 30 degrees or less(e.g., about 25 degrees or less, about 20 degrees or less, about 15degrees or less, about 12 degrees or less, about 10 degrees or less,about 9 degrees or less, about 8 degrees or less, about 7 degrees orless, about 6 degrees or less, about 5 degrees or less, about 4 degreesor less, about 3 degrees or less) in the viewer's visual field. Thesolid angles subtended in the horizontal and vertical viewing planes maybe the same or different.

The dots are formed by arrays of protuberances on a surface of each oflenses 110 a and 110 b. The protuberances are formed from an opticallytransparent material having a similar refractive index to the underlyinglens, which is 1.60 for polycarbonate. For example, in embodiments wherethe lenses are formed from polycarbonate, the protuberances can beformed from a polymer having a similar refractive index to the PC, suchas from light-activated polyurethane or epoxy based plastics. Inaddition to PC, the lenses themselves can also be made from allyldiglycol carbonate plastic, a urethane-based monomer or other impactresistant monomers. Alternatively, lenses could be made from one of themore-dense high-refractive index plastics with an index of refractiongreater than 1.60.

In some embodiments, the protuberance material is selected to have arefractive index that is within 0.1 (e.g., within 0.09 or less, 0.08 orless, 0.07 or less, 0.06 or less, 0.05 or less, 0.04 or less, 0.03 orless, 0.02 or less, 0.01 or less, 0.005 or less, 0.002 or less, 0.001 orless) of the refractive index of the lens material (e.g., as measured atone or more wavelengths in the visible light range).

The protuberances are sized and shaped so that the dots scatter incidentlight to reduce contrast of an object viewed through the reducedcontrast areas. The protuberances may be substantially spherical,ellipsoidal, or irregularly-shaped. Generally, the protuberances shouldhave a dimension (e.g., diameter, as depicted in FIG. 1B) that issufficient large to scatter visible light, yet sufficiently small so asnot to be resolved by the wearer during normal use. For example, theprotuberances can have a dimension (as measured in the x-y plane) in arange from about 0.001 mm or more (e.g., about 0.005 mm or more, about0.01 mm or more, about 0.015 mm or more, about 0.02 mm or more, about0.025 mm or more, about 0.03 mm or more, about 0.035 mm or more, about0.04 mm or more, about 0.045 mm or more, about 0.05 mm or more, about0.055 mm or more, about 0.06 mm or more, about 0.07 mm or more, about0.08 mm or more, about 0.09 mm or more, about 0.1 mm) to about 1 mm orless (e.g., about 0.9 mm or less, about 0.8 mm or less, about 0.7 mm orless, about 0.6 mm or less, about 0.5 mm or less, about 0.4 mm or less,about 0.3 mm or less, about 0.2 mm or less, about 0.1 mm).

Note that for smaller protuberances, e.g., having a dimension that iscomparable to the wavelength of light (e.g., 0.001 mm to about 0.05 mm),the light scattering may be considered Raleigh or Mie scattering. Forlarger protuberances, e.g., about 0.1 mm or more, light scattering maybe due to a lensing effect of the protuberance, such as due to focusingby a lens with a very small radius of curvature to a point far in frontof the user's retina. In such a case, when the light from eachprotuberance reaches the user's retina, it has substantially divergedfrom its point of focus and is not resolvable as an image by the user.

In general, the dimension of the protuberances may be the same acrosseach lens or may vary. For example, the dimension may increase ordecrease as a function of the location of the protuberance, e.g., asmeasured from the clear aperture and/or as a function of distance froman edge of the lens. In some embodiments, the protuberance dimensionsvary monotonically as the distance from the center of the lens increases(e.g., monotonically increase or monotonically decrease). In some cases,monotonic increase/decrease in dimension includes varying the diameterof the protuberances linearly as a function of the distance from thecenter of the lens.

The protuberances shown in FIG. 1B are arranged on a square grid, spacedapart by a uniform amount in each direction. This is shown by D_(y) inthe y-direction and D_(x) in the x-direction. In general, the dots arespaced so that, collectively, they provide sufficient contrast reductionin the viewer's periphery for myopia reduction. Typically, smaller dotspacing will result in greater contrast reduction (provided adjacentdots do not overlap or merge). In general, D_(x) and D_(y) are in arange from about 0.05 mm (e.g., about 0.1 mm or more, about 0.15 mm ormore, about 0.2 mm or more, about 0.25 mm or more, about 0.3 mm or more,about 0.35 mm or more, about 0.4 mm or more, about 0.45 mm or more,about 0.5 mm or more, about 0.55 mm or more, about 0.6 mm or more, about0.65 mm or more, about 0.7 mm or more, about 0.75 mm or more) to about 2mm (e.g., about 1.9 mm or less, about 1.8 mm or less, about 1.7 mm orless, about 1.6 mm or less, about 1.5 mm or less, about 1.4 mm or less,about 1.3 mm or less, about 1.2 mm or less, about 1.1 mm or less, about1 mm or less, about 0.9 mm or less, about 0.8 mm or less). As anexample, dot spacing can be 0.55 mm, 0.365 mm, or 0.240 mm.

While the protuberances shown in FIG. 1B are arranged with equal spacingin the x- and y-directions, more generally spacing in each direction maybe different. Furthermore, protuberances may be arrayed in grids thatare not square. For example, hexagonal grids may be used. Non-regulararrays are also possible, e.g., random or semi-random dot placement maybe used. In the case of a random pattern dimensions given would be theaverage separation of the dots in X and Y directions.

While the dots are depicted as have circular footprints in FIG. 1B, moregenerally the dots can have other shapes. For example, the dots can beelongated in one direction (e.g., in the x-direction or y-direction),such as in the case of elliptical dots. In some embodiments, the dotsare random on shape.

It is believed that light from a scene that is incident on the lenses inreduced contrast areas 130 a and 130 b between the dots contributes toan image of the scene on the user's retina, while light from the sceneincident on the dots does not. Moreover, the light incident on the dotsis still transmitted to the retina, so has the effect of reducing imagecontrast without substantially reducing light intensity at the retina.Accordingly, it is believed that the amount of contrast reduction in theuser's peripheral field of view is correlated to (e.g., is approximatelyproportional to) the proportion of the surface area of thereduced-contrast areas covered by the dots. Generally, dots occupy atleast 10% (e.g., 20% or more, 30% or more, 40% or more, 50% or more,such as 90% or less, 80% or less, 70% or less, 60% or less) of the area(as measured in the x-y plane) of reduced contrast area 130 a and 130 b.

In general, the dot pattern reduces the contrast of images of objects inthe wearer's peripheral vision without significantly degrading theviewer's visual acuity in this region. Here, peripheral vision refers tothe field of vision outside of the field of the clear aperture. Imagecontrast in these regions can be reduced by 40% or more (e.g., 45% ormore, 50% or more, 60% or more, 70% or, more, 80% or more) relative toan image contrast viewed using the clear aperture of the lens asdetermined. Contrast reduction may be set according to the needs of eachindividual case. It is believed that a typical contrast reduction wouldbe in a range from about 50% to 55%. Contrast reductions of lower than50% may be used for very mild cases, while subjects who are morepredisposed might need a higher than 55% contrast reduction. Peripheralvisual acuity can be corrected to 20/30 or better (e.g., 20/25 orbetter, 20/20 or better) as determined by subjective refraction, whilestill achieving meaningful contrast reduction.

Contrast, here, refers to the difference in luminance between twoobjects within the same field of view. Accordingly, contrast reductionrefers to a change in this difference.

Contrast and contrast reduction may be measured in a variety of ways. Insome embodiments, contrast can be measured based on a brightnessdifference between different portions of a standard pattern, such as acheckerboard of black and white squares, obtained through the clearaperture and dot pattern of the lens under controlled conditions.

Alternatively, or additionally, contrast reduction may be determinedbased on the optical transfer function (OTF) of the lens (see, e.g.,http://www.montana.edu/jshaw/documents/18%20EELE582_S15_OTFMTF.pdf). Foran OTF, contrast is specified for transmission of stimuli in which lightand dark regions are sinusoidally modulated at different “spatialfrequencies.” These stimuli look like alternating light and dark barswith the spacing between bars varying over a range. For all opticalsystems the transmission of contrast is lowest for the sinusoidallyvarying stimuli having the highest spatial frequencies. The relationshipdescribing the transmission of contrast for all spatial frequencies isthe OTF. The OTF can be obtained by taking the Fourier transform of thepoint spread function. The point spread function can be obtained byimaging a point source of light through the lens on to a detector arrayand determining how light from a point is distributed across thedetector.

In the event of conflicting measurements, the OTF is technique ispreferred.

In some embodiments, contrast may be estimated based on the ratio of thearea of the lens covered by dots compared to the area of the clearaperture. In this approximation, it is assumed that all the light thathits the dots becomes uniformly dispersed across the entire retinalarea, which reduce the amount of light available in lighter areas of animage and this adds light to darker areas. Accordingly, contrastreduction may be calculated based on light transmission measurementsmade through the clear aperture and dot pattern of a lens

Generally, ophthalmic lenses 110 a and 110 b can be clear or tinted.That is, the lenses may be optically transparent to all visiblewavelengths, appearing clear and/or colorless, or may include a spectralfilter, appearing colored. For example, ophthalmic lenses may include afilter that reduces the amount of red light transmitted to the wearer.It is believed that excessive stimulation of L cones in a person's eye(especially in children), may result in non-optimal eye lengthening andmyopia. Accordingly, spectrally filtering red light using the ophthalmiclenses may further reduce myopia in a wearer.

Spectral filtering may be provided by applying a film to a surface ofthe lenses. Films may be applied by physically depositing material ontoa lens surface, coating a layer of material on the surface, orlaminating a preformed film onto the surface. Suitable materials includeabsorptive filter materials (e.g., dyes) or multilayer films, providinginterference filtering. In some embodiments, spectral filtering may beprovided by including a filtering material in the lens material itselfand/or including a filtering material in the material used to form theprotuberance.

Referring to FIG. 2, the effect of spectral filtering and contrastreduction from the dot pattern is shown by viewing black text on a whitebackground using eyeglasses 210. The white background to the text takeson a green appearance due to the filtering of red wavelengths from bythe eyeglasses. Image contrast is unaffected at clear apertures 220 aand 220 b, but is reduced elsewhere in the viewer's visual frame.

In general, dots can be formed from lenses in a variety of waysincluding UV LED Direct-to-Substrate Printing, pad printing, hotstamping and screen printing technologies. In some embodiments, dots areformed by inkjetting a curable material onto a surface of a blankophthalmic lens and then curing the material to set the dot pattern.Referring to FIG. 3A, an inkjetting and curing system 300 includes aninkjet printer 320 and a computer 310 in communication with the printer.Printer 320 includes a controller 330, a reservoir 340, an inkjetprinthead 350, and a stage 360. Stage 360 supports a lens 301 andpositions the lens relative to printhead 350. Reservoir 340 storesuncured material for inkjetting. Examples of curable material suitablefor inkjetting includes various commercially-available proprietarymonomers and oligomers that are cross-linked together, byphotopolymerisation.

During operation, printhead 350 receives uncured material from reservoir340.

Stage 360 moves lens 301 relative to printhead 350 (as depicted byarrows 361) while printhead 350 ejects drops of uncured material 302toward the lens. Either the stage and/or printhead may be the movingpart during this process. Drop volume varies depending on the desiredprotuberance dimensions. Drop volumes may be in a range from 0.001 mm³to 0.015 mm³ (e.g., about 0.002 mm³, about 0.003 mm³, about 0.004 mm³,about 0.005 mm³, about 0.006 mm³, about 0.008 mm³, about 0.010 mm³,about 0.012 mm³). Upon contact with the lens surface, the drops wet thesurface forming uncured protuberances 305. Alternatively, in someembodiments, stage 360 remains stationary while actuators move theprinthead relative to the lens.

System 300 also includes a UV lamp 370. Stage 360 positions the lensadjacent lamp 370 so that the lamp can cure the deposited material,forming the final protuberances. Examples of suitable UV lamps includeLEDs emitting in the wavelength range of 360-390 nm.

Controller 330 is in communication with reservoir 340, printhead 350,stage 360, and UV lamp 370 and coordinates the operation of each tofacilitate printing and curing of the drops. Specifically, controller330 controls the relative motion between printhead 350 and stage 360,the inkjet drop ejection frequency, and drop volume so that system 300forms the desired dot pattern on lens 301. Controller 330 may alsocontrol the temperature of the uncured material (e.g., by a heaterassociated with reservoir 340 or elsewhere) to control the viscosity ofthe uncured material. The user inputs the drop pattern via computer 310,which generates corresponding control signals for the printer andcommunicates the signals to controller 330.

Commercially-available inkjet printers may be used. Suitable inkjetprinters include Roland DGA (Irvine, Calif.) and Mimaki (Suwanee, Ga.)brands of UV LED Direct-to-Substrate Printers.

Inkjetting dot patterns allows an eye care professional to personalizedot patterns for a patient in an inexpensive and efficient manner.Referring to FIG. 3B, personalized eyeglasses are provided by a sequence380 that may be performed entirely at the eye care professional'soffice. In a first step 381, the eye care professional determines thepatient's prescription, e.g., by refracting the subject. This stepdetermines the power of the ophthalmic lens upon which the dot patternis formed. The patient also chooses their eyeglass frames in the sameway they would for regular prescription glasses.

In the next step 382, the eye care professional selects a dot patternsuitable for the patient. Parameters for the dot pattern that can bevaried include, for example, dot size, dot density, clear aperture sizeand shape, and location of the clear aperture on the lens. Each of thesemay be individualized depending on the desired amount of contrastreduction in the peripheral vision and clear aperture angular range. Anexemplary dot pattern is shown in FIG. 3C. This pattern prints dots overan area larger than most lens blanks, ensuring complete coverage of thelens surface by the dot pattern. Commercial software suitable forgenerating images (e.g., Microsoft Office products such as Visio,PowerPoint, or Word) may be used in conjunction with standard inkjetdriver software to generate control signals for the inkjet printer.Alternatively, custom software can be used by the eye care professionalto input the chosen parameters for the pattern into the ink jetprinter's computer.

Next, in step 383, the ink jet printer deposits drops of uncuredmaterial in accordance with signals from the computer to form dots inthe desired pattern. In step 384, the printed pattern is then exposed tocuring radiation. In some embodiments, the center of the dot pattern,such as the clear center, is aligned to the optical center of the lens.This can be achieved, for example, by measuring and marking the opticalcenter using a lensometer and aligning the print pattern with the markedoptical center. In certain implementations, the optical center of thelens is first marked, then edged in a circular shape, such that theoptical center is aligned to the geometric center of the circular lens.Drops are then printed on the lens so that the dot pattern is centeredon the circular lens, which now corresponds to the optical center.Alternatively, or additionally, lens blanks can be made or chosen suchthat the optical center always matches the geometric center of the lens.

Finally, in step 385, the lenses are edged and mounted in the frames.

In some implementations, the lenses can be mounted in the frames and theframes fit to the wearer before the dots are cured. In this way, theprinted dot pattern can be cleaned off the lens and the reprinted ifnecessary.

Referring to FIG. 3D, in some implementations, a jig 390 is used tosupport multiple lens blanks during lens manufacturing. Jig 390 includesa tray 391 that features an array of lens holders 392 on one surface,each sized to securely hold a lens. For example, if 60 mm diameter lensblanks are used, the lens holders each have a diameter of 60 mm totightly hold a respective lens. During operation, jig 390 including oneor more lenses is positioned on stage 360. The jig holds each lens inprecise location so that system 300 can accurately jet onto the lenses'surface. In addition, the jig allows for manufacturing multiple lensesper batch. While the jig in FIG. 3D includes 48 lens holders, generally,jigs can be designed to hold any number of lenses subject to thephysical constraints imposed by the ink jetting system. Many sizes ofjigs are possible, for example jigs that accommodate about 24 lenses,about 48 lenses, about 100 lenses, about 200 lenses, about 300 lenses,about 400 lenses, about 500 lenses, or more than 500 lenses per run.

FIGS. 4A-4C show photographs of a lens printed using the pattern of FIG.3C. FIG. 4A shows the entire lens, while FIGS. 4B and 4C show anenlarged portion of the dot pattern, the portion in FIG. 4C includingthe clear aperture.

Other methods for forming protrusions are also possible. For example,transfer or lithographic printing can be used instead of inkjetting.Transfer printing involves forming the protrusions on a differentsubstrate and then transferring them to the surface of the lens in aseparate process step. Lithographic printing may involve forming acontinuous, uniform layer of the protrusion material on the lens surfaceand then patterning that layer to form the dot pattern. Optical orcontact lithography can be used to pattern the layer. Alternatively, theprotrusions can be molded on the lens surface using the same moldingprocess used to form the lens. In this case, the protrusions are part ofthe lens mold. In some embodiments, the dot pattern may be provided by afilm that is laminated onto a surface of the lens.

While the dot pattern in the embodiments described above are protrusionsformed on a surface of the ophthalmic lens, other implementations thatprovide comparable optical properties and lens durability are alsopossible. For example, in some embodiments, contrast reduction isprovided by arrays of recesses in a lens surface. The recesses can havedimensions similar to those of the protuberances described above.Recesses can be formed using a variety of techniques, such as etching(e.g., physical etching or chemical etching) or ablating material fromthe lens surface (e.g., using laser radiation or a molecular or ionbeam). In some embodiments, recesses are formed when molding the lens.

Alternatively, or additionally, dot patterns can be embedded in the lensmaterial itself. For example, transparent beads of appropriate size canbe dispersed in the lens material when the lens is molded, where therefractive index of the bead material and bulk lens material differ. Theclear aperture is formed from bulk lens material only.

In some embodiments, contrast reduction is produced by other diffusingstructures, such as a roughened surface. Holographic diffusers or groundglass diffusers may be used. In some embodiments, a diffuser may beprovided by a film that is laminated onto a surface of the lens.

While the foregoing description pertains to ophthalmic lenses foreyeglasses, the principles disclosed may be applied to other forms ofophthalmic lenses, such as contact lenses. In some embodiments, dotpatterns may be provided on contact lenses to provide similartherapeutic effects. The size and spacing of dots in a contact lens dotpattern may be sized so that they subtend comparable solid angles in auser's visual field to the dot patterns described for eyeglass lensesabove.

Dot patterns may be formed on contact lenses in a variety of ways. Forexample, dot patterns may be printed or transferred to a contact lenssurface using the techniques described above. Alternatively, the dotpatterns may be formed by dispersing scattering materials in the contactlens.

In some embodiments, dots are formed on one or both surfaces of acontact lens by exposing a contact lens surface to laser radiation. Thelaser radiation locally ablates the contact lens material at thesurface, leaving a small depression. By selectively exposing the contactlens surface to laser radiation, a dot pattern can be formed on thesurface. For example, the laser's beam can be moved relative to thesurface while the beam is pulsed. Relative motion between the beam andthe contact lens surface can be caused by moving the beam while leavingthe surface fixed, moving the surface while leaving the beam fixed, ormoving both the beam and the surface.

Referring to FIG. 13, a laser system 1300 for forming dots on a surfaceof a lens includes a laser 1320, a beam chopper 1330, focusing optics1340, a mirror 1350, and a stage 1370. Laser 1320 directs a laser beamtowards mirror 1350, which deflects the beam towards a contact lens 1301which is positioned relative to the mirror 1350 by stage 1370. Anactuator 1360 (e.g., a piezoelectric actuator) is attached to mirror1350. The stage includes a curved mounting surface 1380 which supportscontact lens 1301. Laser system 1300 also includes a controller (e.g., acomputer controller) in communication with laser 1320, beam chopper1330, and actuator 1360.

Beam chopper 1330 and focusing optics 1340 are positioned in the beampath. Chopper 1330 periodically blocks the beam so that contact lens1301 is exposed to discrete pulses of laser light. Focusing optics 1340,which generally includes one or more optically powered elements (e.g.,one or more lenses), focuses the beam to a sufficiently small spot onthe surface of contact lens 1301 so that the area ablated by the beam onthe lens surface corresponds to the desired dot size. Actuator 1360changes the orientation of mirror 1350 with respect to the beam to scanthe pulsed beam to different target points on the contact lens surface.Controller 1310 coordinates the operation of laser 1320, chopper 1330,and actuator 1360 so that the laser system form a predetermined dotpattern on the contact lens.

In some implementations, stage 1370 also includes an actuator. The stageactuator can be a multi-axis actuator, e.g., moving the contact lens intwo lateral dimensions orthogonal to the beam propagation direction.Alternatively, or additionally, the actuator can move the stage alongthe beam direction. Moving the stage along the beam direction can beused to maintain the exposed portion of the lens surface at the focalposition of the beam, notwithstanding the curvature of the lens surface,thereby maintaining a substantially constant dot size across the lenssurface. The stage actuator can also be controlled by controller 1310,which coordinates this stage motion with the other elements of thesystem. In some embodiments, a stage actuator is used in place of themirror actuator.

Generally, laser 1320 can be any type of laser capable of generatinglight with sufficient energy to ablate the contact lens material. Gaslasers, chemical lasers, dye lasers, solid state lasers, andsemiconductor lasers can be used. In some embodiments, infrared lasers,such as a CO₂ laser (having an emission wavelength at 9.4 μm or 10.6 μm)can be used. Commercially-available laser systems can be used such as,for example, CO₂ laser systems made by Universal Laser Systems, Inc.(Scottsdale, Ariz.), (e.g., the 60 W VLS 4.60 system).

The pulse duration and pulse energy are typically selected to ablate anamount of material from the contact lens surface to provide a dot of adesired size. An example dot pattern for a contact lens is shown in FIG.14A. Here, contact lens 1400 includes a clear aperture 1410, areduced-contrast region 1420, and a clear outer region 1430.Reduced-contrast region 1420 is an annular region having an innerdiameter ID and an outer diameter OD. ID corresponds to the diameter ofclear aperture 1410. The contact lens has a lens diameter, LD, which isgreater than OD.

Typically, ID is less than the user's pupil diameter under normal indoorlighting conditions (e.g., such as typical classroom or office lightingin which a user is able to easily read text from a book). This ensuresthat, under such lighting conditions, image contrast in the user'speripheral visual field is reduced. In some embodiments, ID is in arange from about 0.5 mm to about 2 mm (e.g., in a range from about 0.75mm to about 1.75 mm, in a range from about 0.9 mm to about 1.2 mm, about0.6 mm or more, about 0.7 mm or more, about 0.8 mm or more, about 0.9 mmor more, about 1 mm or more, about 1.1 mm or more, about 1.2 mm or more,about 1.9 mm or less, about 1.8 mm or less, about 1.7 mm or less, about1.6 mm or less, about 1.5 mm or less, about 1.4 mm or less, about 1.3 mmor less).

Generally, OD is sufficiently large so that the reduced-contrast regionextends beyond the user's pupil under normal indoor lighting conditions.In some embodiments, OD is about 2.5 mm or more (e.g., about 3 mm ormore, about 4 mm or more, about 5 mm or more, such as about 10 mm orless, about 8 mm or less, about 7 mm or less, about 6 mm or less).

Generally, the dimensions and spacing between the dots in the contactlenses are selected so as to provide the desired optical effect (e.g.,as described above), subject to the constraints of the method used toform the dots. In some embodiments, the dots can have a maximum lateraldimension in a range from about 0.005 mm or more (e.g., about 0.01 mm ormore, about 0.015 mm or more, about 0.02 mm or more, about 0.025 mm ormore, about 0.03 mm or more, about 0.035 mm or more, about 0.04 mm ormore, about 0.045 mm or more, about 0.05 mm or more, about 0.055 mm ormore, about 0.06 mm or more, about 0.07 mm or more, about 0.08 mm ormore, about 0.09 mm or more, about 0.1 mm) to about 0.5 mm or less(e.g., about 0.4 mm or less, about 0.3 mm or less, about 0.2 mm or less,about 0.1 mm).

The spacing of the dots can also vary so as to provide the desiredoptical effect. Typically, the spacing of the depressions (i.e., asmeasured between the center of adjacent depressions) are in a range fromabout 0.05 mm (e.g., about 0.1 mm or more, about 0.15 mm or more, about0.2 mm or more, about 0.25 mm or more, about 0.3 mm or more, about 0.35mm or more, about 0.4 mm or more, about 0.45 mm or more) to about 1 mm(e.g., about 0.9 mm or less, about 0.8 mm or less, about 0.7 mm or less,about 0.6 mm or less, about 0.5 mm or less).

The relative area of dots in the reduced-contrast region can vary asdescribed above for eyeglass lenses.

LD corresponds to the diameter of the contact lens and is typically in arange from about 10-20 mm. Generally, LD is greater than OD by at least1 mm or more (e.g., about 2 mm or more, about 3 mm or more, about 4 mmor more, about 5 mm or more, about 6 mm or more, about 7 mm or more,such about 8 mm). Including at least some space at the edge of thecontact lens that does not include dots ensures that the dots do notreduce the integrity of the contact lens at its edge (e.g., by tearing)or reducing the integrity of the seal between the contact lens and theuser's eyeball.

While the contact lens dot pattern shown in FIG. 14A features dots thateach have the same size and the same spacing between adjacent dots,other dot arrangements are possible. For example, referring to FIG. 14B,a contact lens 1450 features dots having varying sizes. Here, contactlens 1450 includes a clear aperture 1460, a reduced-contrast region1470, and a clear outer region 1480. Reduced-contrast region 1470includes a dot pattern in which the size of the dots increases as theradial distance of the dot position with respect to the center of thelens increases. Accordingly, dots 1471 closest to clear aperture 1460are the smallest, while dots 1472 closest to outer region 1480 are thelargest.

Although system 1300 is shown as ablating a contact lens, moregenerally, laser ablation can be used for eyeglass lenses too.

While myopia progression and treatment efficacy may be monitored insubjects using a variety of techniques (e.g., including subjectiverefraction and/or eye length measurements), it is believed that changesin choroidal thickness (i.e., an increase in the choroidal thickness) isa reliable biomarker for this purpose. Choroid thickness can be measuredusing optical coherence tomography (OCT). Exemplary deep field OCTimages showing the choroid thickness in a subject are shown in FIGS. 5Aand 5B. The choroid, shown in cross-section between the two yellowcurves spanning the image field from left to right. Because OCT imagesmay have variable magnification, an internal landmark that doesn'tchange thickness over the course of treatment may be used as a referencewhen making thickness measurements. An example of such a landmark is theretinal pigmented epithelium (RPE) layers between the choroid and theretina, whose thickness is indicated by the red line shown in FIG. 5B.

EXAMPLES Initial Study/Comparative Example

In prior investigations, it was found that proof-of-concept eyeglassesusing diffusing filters attached to the surface of the lenses could slowaxial length growth in subjects but there were a number of challenges.The filter used was a commercially available Bangerter Occlusion Foil(“BOF”). These were diffusers made of thin flexible static vinyl filmwhich was trimmed to match the lens shape and adhered to the right lens.The “foil” used was “BOF-0.8 Acuity of 20/25” which, as the nameimplies, nominally reduced best corrected acuity to 20/25. However, inpractice, acuity of subjects who could be best corrected in the range of20/15-20/20, tested in the range 20/30-20/40 with the BOF-0.8 filter inplace. The subjects of this study wore the diffuser unilaterally on oneeye was because of the large reduction in acuity it produced and therewas concern about the tolerability and safety of wearing spectacles thatreduced acuity to 20/30-40 binocularly. By making the diffuser armmonocular, subjects of this study were able to function normally becausethey had one eye they could use for high acuity vision. However,ideally, in a commercial product, the treatment should be done to botheyes simultaneously.

Another problem with the Initial Study was that the vinyl filters coulddetach from the lenses accidentally. In order to deal with this problem,in the trial, each subject was provided with two pairs of glasses withthe instruction to use the second pair if the filter came off the firstpair. Then, it was possible to supply the subject with a new backuppair. Ideally, in a commercial product the diffuser should be a durableas standard lenses.

New Study

Prototype lenses were designed to address problems with the spectaclesused in the Initial Study and at the same time maintain or improveefficacy in slowing growth of axial length. It is believed that the mainreason the BOF-0.8 filters reduced acuity so drastically was because ofthe very poor optical quality of the vinyl film itself. Non-uniformitiesin thickness produced a “wavy” pattern that distorted the image makingvision difficult. However, it was believed this degradation of the imagedid not have any therapeutic value. Thus, one goal for the prototypelenses of the new study was to eliminate any kind of film applied to theeyeglasses and provide the diffuser as a permanent part of the lensitself. In the new design, the diffuser component of these lenses servesthe purpose of lowering contrast of the image but every other aspect ofthe optical quality is substantially the same as the standard of care.

A first step in the development of the eyeglasses was to produce a lensthat replicated the amount of diffusion (and presumably the therapeuticvalue) of the BOF-0.8 filter but had all the other optical properties ofa standard (i.e., non-diffusing) lens. Efficacy of the new prototypeswere compared with the BOF-0.8 filter of the Initial Study which wasused as the standard for efficacy. In order to reduce the length of thestudy on new prototypes, choroid thickening measured using opticalcoherence tomography (OCT) was used as a biomarker for treatmentefficacy. The choroid was imaged using OCT and it was demonstrated thatthe BOF-0.8 filter produced a thickening of the choroid that could beaccurately measured. Images from this study are shown in FIGS. 6A-6D.OCT non-invasively provides a cross-sectional view of the retina throughthe fovea. Several layers can be resolved including the inner limitingmembrane nerve fiber layer (NFL), ganglion cell layer (GCL), innerplexiform layer (IPL), inner nuclear layer (INL), junction between theinner and outer segment of the photoreceptors (IS/OS PR), outer nuclearlayer (ONL), retinal pigment epithelium (RPE). The very deepest layer isthe choroid. FIGS. 6A and 6C show the unsegmented images of the retinafrom one subject before and after treatment with the BOF-0.8 filter. Arelative thickening of the choroid layer is evident post-treatmentcompared to pretreatment. FIGS. 6B and 6D include segment lines (in red)showing the outer bounds of the choroid. FIG. 6C shows the choroid atday 39 post-treatment. FIG. 6D shows the choroid at day 39post-treatment with the outerbound of the choroid demarcated. Thicknesswas measured as the distance from the boundary line to the RPE boundary.

FIG. 7 shows a plot of relative choroid thickness as a function oflocation on the retina for this study. A marked post-treatmentthickening (upper, blue curve) of the choroid is evident across theretina compared to the pre-treatment measurements (lower, black curve).

Example: Prototype I

A first prototype eyeglasses, prototype I, was developed to provide alens that incorporated diffusive elements and lowered the contrast ofthe image substantially the same amount as the BOF-0.8 filter whilebeing practical and durable and free of the many optical imperfectionsof the vinyl substrate of the BOF-0.8 filter. The lens for formed byinkjet printing a dot pattern on lenses using a UV-curable material.Printers from the Roland DG VersaUV line of inkjet printers and MimakiUV flat bed printers were both used in different versions of prototypeI. The UV-curable materials were also obtained from Roland and Mimaki.

The lenses were clear polycarbonate, shatterproof lenses, without anyspectral filtering. The dot pattern was printed on a square grid havinga spacing of 0.55 mm. The volume of each dot was 0.004 mm³. The dotpattern covered the entire lens; no clear aperture remained. The printedpattern was cured using UV LEDs emitting in the range 365 nm-385 nm. Aphotograph of an example prototype I lens is shown in FIG. 8.

We tested prototype I lens using a within-subjects protocol. A smallnumber of subjects were recruited and refracted to their best correctedvisual acuity. The hypothesis that the initial reduction in axial lengthwas the result of choroidal thickening was tested with an OCT study. Forthis,

After a week of baseline measurements, subjects wore glasses with anuntreated left eye (OS) lens and a BOF-0.8 filter attached to the righteye (OD) lens. After four weeks, subjects then switched to the newprototype lenses on their left eyes (OS) and the right eyes woreuntreated lenses. The absolute difference between the choroid thicknessof the left and right eyes (OD-OS) increased significantly after a monthof BOF-0.8 filter wear over the right eye. When the OD glasses wereremoved and the OS eye was treated with prototype I there was acorresponding significant decrease in the axial length of OS (p=0.0083)and an increase in the OD-OS value (p=0.0032). There was no significantdifference between the effectiveness of prototype I and the BOF-0.8filter with respect to producing an increase in choroid thickness.However, there was a drastic difference in best corrected visual acuitywhen wearing our prototype I compared to the BOF-0.8 filter.

Example 2: Prototype II

The goal for prototype II was to produce a lens that would allowmeasured best corrected visual acuities of 20/15-20/20 but haveeffectiveness as good or better than the BOF-0.8 filter. To this end,prototype II lenses were produced by modifying the prototype I dotpattern to incorporate a small central clear area. The dots were formedon a square grid pattern with a spacing of 0.55 mm. The clear aperturewas formed in with a circular shape of diameter 3.8 mm. A photograph ofa prototype II lens is shown in FIG. 9.

When the glasses were fitted, the clear area was positioned to match thepupil allowing the wearer to look through the clear area when viewingstraight ahead. Subjects who were best corrected to 20/15-20/20 testedas 20/15-20/20 when wearing prototype II and reading the eye chartlooking through the clear area.

We tested prototype II with the clear area against prototype I byrecruiting a small number of subjects and having them wear the lens withthe clear area on the left eye and the lens without on the right eye. Wethen compared increases in choroidal thickness between the two eyes andfound no difference between the lenses with the clear area and the lenswithout. This demonstrated that it is possible to design a diffuser lenswithout spectral light filtering, that allowed subjects to test withbest corrected acuities of 20/15-20/20 and still maintain theeffectiveness (as measured by increases in choroid thickness) of theoriginal lens used in the Initial Study.

Example 3: Prototype III

Further improvements were explored to simultaneously maximizetolerability and effectiveness. We felt that the larger the clear areathe more tolerable the prototype would be but also hypothesized thatincreasing the peripheral contrast reduction might increase theeffectiveness. Thus, we experimented with these two variables producinganother prototype: prototype III. Like prototypes I and II, prototypeIII did not have a spectral light filtering. The dot pattern forprototype III was modified to include a larger clear aperture and agreater reduction in contrast outside the clear area than prototype II.In particular, the clear aperture was enlarged to a 5.0 mm diameter andthe square grid spacing reduced to 0.365 mm. Dot size remained the sameas prototype II. A photograph of a prototype III lens is shown in FIG.10.

A design goal was to develop a prototype that allows good vision thatchildren and their parents are happy and comfortable with. Visual acuitywith prototype III for children with best corrected acuity of20/15-20/20 was 20/15-20/20 when vision was tested viewing through theclear aperture of the lens. We also tested acuity “off-axis” with thesubject viewing through the peripheral diffuser. Subjects with bestcorrected acuity of 20/15-20/20 through the clear aperture demonstrated20/20-20/25 vision when viewing through the diffusing area.

We initiated a small trial with the prototype III lens worn binocularly.The main objective of the lens was to assay durability and tolerabilityof the lens. The trial had one arm. Subjects were aged 7 to 10 years ofage with a history of myopic progression. Subjects were all referred tous by ophthalmologists because parents were concerned about rapidlyprogressing myopia in their children. The study had a single site, whichwas ophthalmology research at the University of Washington in Seattle. 8children were enrolled. Preliminary results for 4 children who passed 6month wearing the glasses were obtained, monitoring axial length with anoptical biometer, the IOLMaster from Carl Zeiss Meditec. Children werealso asked to keep a journal documenting how many hours a day they wearthe lenses and noting any problems or concerns they had with theeyeglasses.

When subjects came to the lab for axial length measurements, we viewedtheir journal and inspected the eyeglasses for any signs change ordeterioration. We also asked the subjects and their parents if they hadany problems or concerns with the eyeglasses. There were no notedproblems with the durability of the eyeglasses and the subjects andparents had no complaints.

However, referring to FIG. 12, it is interesting to compare axial growththe subjects wearing prototype III with the results of the Initial Studyat 6 months. This figure shows a bar chart comparing the change indiopters after 180 days for subjects' eyes. The first bar represents thecontrol eyeglasses and the second bar represents the original diffusereyeglasses from the Initial Study. The third bar represents PrototypeIII after 6 months for the four children who completed 6 months in thestudy.

What we have demonstrated is that we are able to manufacture stable anddurable spectacles that allow 20/15-20/20 vision. In this small group ofsubjects were very satisfied with the spectacles and they show a slowrate of progression after 6 months.

Example 4: Contact Lenses

Dot patterns were formed on contact lenses as follows. In each case, a−7.5 D contact lens was positioned on a ball bearing on the stage of aVLS 4.60 CO2 laser system (Universal Laser Systems, Inc., Scottsdale,Ariz.). The lens diameter in each case was 14 mm.

Contact lenses were exposed at 5% power, 10% power, and 20% powersettings respectively. In each exposure, the laser scan speed was set to25% and the resolution set to 0.002 inches. The exposure area had anouter diameter of 12.7 mm and an inner diameter of 1 mm. The exposurepattern within the area was a square grid with a grid spacing of 0.0116inches.

A visible dot pattern was formed for 5% and 10% power settings. The 20%power setting resulting in cutting through the contact lens.

A photograph of one of the contact lenses is shown in FIG. 15A. The dotpattern is clearly visible.

Example 5: Eyeglass Lenses Using Laser Ablation

Dot patterns were formed on several Trivex eyeglass lenses using a 60 W,10.6 μm, VLS 4.60 CO2 laser system (Universal Laser Systems, Inc.,Scottsdale, Ariz.). Lenses were exposed various powers between 5% and40% and in both raster and vector print modes. The laser was set at1,000 PPI. Speed settings were 25% or 100%.

A photograph of a lens exposed in vector mode is shown in FIG. 15B. Thedot pattern in this example, which was printed in vector mode, isclearly visible.

A number of embodiments are described. Other embodiments are in thefollowing claims.

What is claimed is:
 1. Eyeglasses, comprising: a first ophthalmic lensmounted in eyeglass frames, the first ophthalmic lens comprising a firstregion and a second region surrounding the first region, the secondregion of the first ophthalmic lens comprising a plurality ofspaced-apart light scattering centers and the first region of the firstophthalmic lens being free from light scattering centers; and a secondophthalmic lens mounted in the eyeglass frames, the second ophthalmiclens comprising a first region and a second region surrounding the firstregion, the second region of the second ophthalmic lens comprising aplurality of spaced-apart light scattering centers and the first regionof the second ophthalmic lens being free from light scattering centers,wherein, the scattering centers of the first and second ophthalmiclenses have a maximum dimension in a range from 0.08 mm to 0.5 mm andare spaced apart by 0.8 mm or less, and for incident light transmittedby each ophthalmic lens, the ophthalmic lens scatters light incident onthe light scattering centers.
 2. The eyeglasses of claim 1, wherein foreach ophthalmic lens, the light scattering from the light scatteringcenters reduces a contrast of an image viewed through the second regioncompared with the image viewed through the first region.
 3. Theeyeglasses of claim 2, wherein for each ophthalmic lens, the lightscattering from the light scattering centers reduces a contrast of animage viewed through the second region compared with the image viewedthrough the first region by at least 30%.
 4. The eyeglasses of claim 1,wherein for each ophthalmic lens, the first region is a clear apertureregion located on each lens to provide on-axis vision, wherein eachophthalmic lens has optical power to correct a wearer's on-axis visionto 20/20 or better through the clear aperture.
 5. The eyeglasses ofclaim 4, wherein for each ophthalmic lens, the second region is locationin each lens to provide peripheral vision, wherein for the wearer'speripheral vision through the second region, each ophthalmic lenscorrects the wearer's vision to 20/25 or better.
 6. The eyeglasses ofclaim 1, wherein the eyeglasses reduce the rate of myopia progression ina human subject.
 7. The eyeglasses of claim 1, wherein for eachophthalmic lens, the first region is aligned with a line of sight of awearer of the eyeglasses.
 8. The eyeglasses of claim 1, wherein for eachophthalmic lens in the second region, the light scattering centers arespaced apart by a distance of 0.5 mm or less.
 9. The eyeglasses of claim1, wherein for each ophthalmic lens, the light scattering centers eachhave a maximum dimension of 0.3 mm or less.
 10. The eyeglasses of claim1, wherein for each ophthalmic lens, each light scattering center issubstantially the same size.
 11. The eyeglasses of claim 1, wherein foreach ophthalmic lens in the second region, the light scattering centersare spaced apart by 0.5 mm or less.
 12. The eyeglasses of claim 1,wherein for each ophthalmic lens in the second region, the lightscattering centers are spaced apart by 0.35 mm or less.
 13. Theeyeglasses of claim 1, wherein for each ophthalmic lens in the secondregion, the light scattering centers correspond to at least 10% of anarea of the second region.
 14. The eyeglasses of claim 13, wherein foreach ophthalmic lens in the second region, the light scattering centerscorrespond to 60% or less of the area of the second region.
 15. Theeyeglasses of claim 1, wherein for each ophthalmic lens, the lightscattering centers are arrayed in a grid pattern.
 16. The eyeglasses ofclaim 1, wherein for each ophthalmic lens the first region has adimension of 3 mm or more in at least one direction.
 17. The eyeglassesof claim 16, wherein for each ophthalmic lens, the first region has adimension of 4 mm in at least one dimension.
 18. The eyeglasses of claim1, wherein for each ophthalmic lens, the first region is substantiallycircular.
 19. The eyeglasses of claim 1, wherein for each ophthalmiclens, the light scattering centers are protrusions on a surface of thecorresponding lens.
 20. The eyeglasses of claim 19, wherein for eachophthalmic lens, the protrusions are formed from a transparent material.21. The eyeglasses of claim 1, wherein for each ophthalmic lens, thelight scattering centers are recesses on a surface of the correspondinglens.
 22. The eyeglasses of claim 1, wherein the light scatteringcenters are embedded in a lens material of the first and secondophthalmic lenses.
 23. A method of making the eyeglasses of claim 1,comprising: depositing discrete portions of a material on a surface ofeach lens within the second region; and curing the deposited material toprovide protrusions on the lens surface forming the light scatteringcenters.
 24. The method of claim 23, wherein the material is depositedusing an inkjet printer.
 25. The method of claim 23, wherein thedeposited material is cured using radiation.
 26. A method of treating aneye-lengthening disorder in a human subject, the method comprising:refracting the subject to determine a lens prescription for correctingthe subject's visual acuity; and providing the subject with theeyeglasses of claim 1, wherein the first and second ophthalmic lenseshaving an optical power corresponding to the lens prescription.
 27. Theeyeglasses of claim 1, wherein the scattering centers are arranged in asemi-random or random pattern.
 28. The eyeglasses of claim 1, whereinthe scattering centers are arranged on a non-regular array.